This invention relates to a hair dryer appliance and more particularly to such an appliance which has incorporated therein a simple multiple speed control circuit for providing a four heat, two speed hair dryer.
Many conventional hair dryers provide different heat levels and generally contain a blower or fan which dispenses the heated air from a nozzle on the dryer as directed by the user. Either a variable heater element or a plurality of separate heater elements are provided to obtain different heat levels. Furthermore, in order to provide multiple speeds for the fan, separate motor control circuits are included which may be in the form of speed control potentiometers.
For example, in U.S. Pat. No. Re. 19,724 separate heater, vapor generator and motor control devices are employed which may be selectively switched into the dryer electrical circuit. The motor control circuit includes a rheostat for varying the speed of the motor. Similarly, in U.S. Pat. No. 4,013,083 a potentiometer is employed in series with a motor for controlling its speed and a potentiometer is also connected in series with a heating coil for varying the heat level thereof.
Any additional elements in the circuitry increase the complexity of the dryer, may tend to reduce its reliability as well as its operating life, may increase the size of the dryer and probably most importantly will increase the cost of manufacture and accordingly, the cost to the user.